Dynamical system analysis in modified Galileon cosmology

TL;DR

This paper performs a phase space analysis of modified Galileon cosmology, identifying critical points that describe different cosmic eras and showing stable dark energy solutions consistent with observational data.

Contribution

It introduces a detailed dynamical system analysis for modified Galileon models with exponential coupling functions and specific potentials, revealing stable late-time acceleration solutions.

Findings

Identification of critical points representing different cosmic phases

Stable dark-energy-dominated solutions indicating late-time acceleration

Consistency of model predictions with H(z) and Supernovae Ia data

Abstract

In this paper, we have investigated the phase space analysis in modified Galileon cosmology, where the Galileon term is considered a coupled scalar field, $F(\phi)$. We focus on the exponential type function of $F(\phi)$ and the three well-motivated potential functions $V(\phi)$. We obtain the critical points of the autonomous system, along with their stability conditions and cosmological properties. The critical points of the autonomous system describe different phases of the Universe. In the results of our analysis, we have found the scaling solution for critical points, which determine different evolutionary eras for the Universe. The dark-energy-dominated critical points show stable behavior and indicate the Universe's late-time cosmic acceleration phase. Further, the results are examined with the cosmological data sets of the Hubble rate $H(z)$ and the Supernovae Ia.